Practical example needed

[Guest]

Long time reader with my first question.

Could someone provide me with a practical example of where I would want or need to use Enter On First Depth Cut Only or Exit On Last Depth Cut Only.

[gcode]

do a closed contour toolpath

like running around the outside of a square.

turn on multipass and check keep tool down

With Enter/Exit first depth off

you will get a Leadin/lead out on every pass

with it on..you get one lead in

a direct move to each new pass

and one lead out

[kkominiarek]

I use it all the time.....works as promised.

[Guest]

Thanks guys. I understand how it works in Mastercam. What I don't understand is why I would use it? It's going to screw up the surface finish of the part. Do you use it only to save time on roughing?

[Programinator]

I use it all the time....If your cutting a contour of a part and you want to go around it 2 times. It saves time and helps with the lead in and out mark on the part.

[Colin Gilchrist]

It works really great when you do a ramp contour too...

 

Lead in to the ramp, ramp the contour, lead out before you retract...

 

Just because it is there doesn't mean you need to use it.

 

There are some features in the toolpaths that I've used maybe two or three times in over ten years of running Mastercam.

 

It is really nice to have them available when you do need them though...

[Guest]

When you use Enter On First Depth Cut Only and you are using multiple depth of cuts the end mill plunges leaving a mark. There is something I am not understanding on how to use this.

[Kyle Waters]

Do you have a lead in value set?

[Guest]

I do have a lead in value set. It is fifty percent of the tool and my arc is forty percent. Set to perpendicular, sweep set to fourty five. Entry and Exit are the same. The tool plunges down on the material after the first depth cut is finished and the second cut starts with Enter On First Depth Cut Only checked.

[Bryan Johnson]

I think the point for 1st and last only feature is to save time.

Where you are worried about leaving a mark, you may want to include leadin on each pass, or include an additional finish pass at finial depth.

[Matthew Hajicek - Singularity]

If you're interpolating a hole and you want 1 cut pass + 1 skim pass it's great. There's no good option to use multiple passes or depth cuts (which should have lead-in and lead-out) but keep the tool against the metal between the final cut pass and one or more skim passes though. In this case I usually edit the toolpath to remove the unwanted leads.

[Chris Rizzo]

quote:

---

When you use Enter On First Depth Cut Only and you are using multiple depth of cuts the end mill plunges leaving a mark

---

Correct.

 

The ideal option would be to lead in/out first and last move of depth/multipass roughing, and then have an independent lead in/out for finish passes. We don't have that option yet aside from creating multiple toolpaths or editing.